Closure containers



Dec. 26, 1967 E. BOHLMAN CLOSURE CONTAINERS 2 Sheets-Sheet 1 Filed Dec. 5, 1966 FIG. 3

LOTHHR ER C BOHL IHN I N VEN TOR.

Attorney E. BOHLMAN CLOSURE CONTAINERS Dec. 26, 1967 2 Sheets-Sheet 2 Filed Dec. 5, 1966 LOT/49R axe c BOA/AMEN 1 N VEN TOR.

' Attorney United States Patent 3,360,156 CLOSURE CONTAINERS Lothar Eric Bohlman, Don Mills, Ontario, Canada, as-

signor to Plasticap Limited, Richmond Hill, Ontario, Canada Filed Dec. 5, 1966, Ser. No. 599,162 6 Claims. (Cl. 220-60) ABSTRACT OF THE DISCLOSURE This specification describes a cover or cap means which is particularly adapted to use on aerosol containers or the like, which containers have a crimped, folded flange or similar juncture means between the container body and the top of the container housing the dispensing means therefor. The cap is formed from plastic with a downwardly depending flange on the interior of which, adjacent the lower end is a plurality of spaced apart projections extending inwardly, these projections coact with the lower end of the flange to give a friction or snap fit on the container.

This invention relates to closures for containers and more particularly to caps for aerosol dispensers and the like.

In the prior art there has been provided three main types of caps for these aerosol dispensers or cans. In the first type the cap engages with a peripheral bead adjacent the upper edge of the main body of the can but this type has had the disadvantage that the cap is too easily dislodged, particularly in transportation, by an adjacent can. In the second type the cap interlocks with a shoulder provided in the top wall of the can adjacent the base of the valve. This second type has also not proved entirely satisfactory in that it sometimes interferes with the operation of the valve. The third type of cap engages a ridge or channel provided in the top wall of the can intermediate the base of the valve and the outer bead so that it neither interferes with the valve or is subject to dislodgement as are the two previously described types.

However, most closures of the third type have not proved satisfactory either since they have depended upon the distortion of the cap to effect engagement between the bead and the cap and in others it is more diflicult to remove and locate the cap rather than replace it.

The facility of mounting and removing the cap is only one feature to be considered, the method of production and quantity of material employed must also be such as to provide an economical product. With the first type of cap an obviously greater amount of material is used than with the third type and with the second type some forms require an inner depending skirt for engagement as well as an outer skirt so that again a greater amount of material is required than with the third type.

Another feature, and perhaps most important, is the requirement that the cap 1 be capable of accommodating wide tolerance and be secure when mounted and not easily dislodged.

With these features in mind it is the principal object of the present invention to provide a cap for containers which is economical to produce, easy to mount and remove while accepting a wider tolerance range of cans while being securely attached to the container when mounted.

It is another object of the present invention to provide a cap for a container which has novel means for eifecting engagement between the cap and the container.

In accordance with the present invention, there is provided a cap or closure which is equally easy to put on and remove without substantially any distortion of the cap. This structure is achieved by providing projections 3,360,156 Patented Dec. 26, 1967 on the inner Wall of the cap skirt which extend at a compound angle downwardly so that when the cap is put on the fingers move over the shoulder usually provided on the top or breast of these containers to effect a secure engagement.

With the above, and other objects in view that will hereinafter appear, the nature of the invention will be more clearly understood by reference to the following detailed description the appended claims and the embodiments illustrated in the accompanying drawings in which:

FIGURE 1 is a perspective view from the bottom of one embodiment of a cap in accordance with the present invention;

FIGURE 2 is a sectional view taken along line 22 of FIGURE 1 and serves to illustrate the relationship of projections on a cap to a radial axis;

FIGURE 3 is a sectional view taken along line 3--3 of FIGURE 1 and serves to illustrate the relationship between projections on a cap to an axis normal to the radial axis;

FIGURE 4 is an enlarged fragmentary sectional view of a cap and an aerosol container which serves to illustrate the relationship prior to mounting of the cap;

FIGURE 5 is an enlarged fragmentary sectional view of the cap and container of FIGURE 4 after mounting the cap on the container;

FIGURE 6 is a perspective view from the bottom of an alternate embodiment of a cap in accordance with the present invention;

FIGURE 7 is a sectional view taken along line 77 of FIGURE 6 and serves to illustrate the relationship of projections on a cap to a radial axis; and

FIGURE 8 is a sectional view taken along line 8--8 of FIGURE 6 and serves to illustrate the relationship be tween projections on a cap and an axis normal to a radial axis.

In FIGURE 1 a preferred embodiment of one form of cap is indicated generally at 10. This cap comprises a circular top wall 11 from the periphery of which a peripheral depending skirt 12 extends. The lower edge of skirt 12 is indicated at 13. On the inner surface of skirt 12 adjacent the lower edge 13 thereof there is provided a plurality of inwardly extending finger-like projections such as 14 and 15, 16 and 17. These projections have a generally truncated conical form and extend inward and downward from a peripherally extending ridge 18. This ridge 18 has a height substantially equal to the adjacent base of each of the individual fingers, such as 14, and gradually widens as it proceeds down towards the open end or lower edge of skirt 12 to provide a ridge inwards of the lower edge 13. This ridge provides a measure of strength.

In the preferred form of my invention the caps are made of thermoplastic materials and may be formed by any well-known method of molding. Any of the known moldable plastics may be employed such as cellulose, acetate butyrate, vinyls, polystyrene, acrylic, polyethylene, polyamide, or any other suitable materials. However, it is preferred to make the cap of flexible material so that there will be a capacity in the cap to accommodate errors in the container dimensions. These errors will, of course, be within the limits of the container specification.

It is to be noted that in the embodiment illustrated in FIGURES 1 through 3 the fingers are divided into two series, fingers 14 and 15 being the first and last projections of the first series and fingers 16 and 17, the first and last projections of the second series and these series are spaced apart by diametrically opposed gaps such as 19 and 20. The provision of such gaps is not essential and it is a production convenience. They provide facility of removing the caps from the molds. In the embodiment illustrated in FIGURES 6 through 8 there is no such gap and a continuous series of regularly spaced apart fingers is provided.

As has been mentioned previously, these projections such as 14, 15, 16 and 17 in FIGURES 1 through 3 have a truncatedconical form and they extend downwardly substantially into the same plane as edge 13-. However, it is to be noted and most importantly that these fingers extend at a compound angle to the depending skirt 12. For example, the main axis of projection or finger 30 is inclined at an angle at to a radius 21 shown in dotted outline and at an angle 5 also to an axis 22 extending normally to the radius in the plane of skirt 12. Each finger is similarly inclined. In the preferred embodiments angles on and 5 are each 45 but this specification is merely by way of example and angles of other magnitude may be employed to obtain a similar engagement with various cap diameters.

In the cap illustrated in FIGURES 6, 7 and 8 the same material is employed and for convenience the corresponding parts are correspondingly numbered. However, there are two main distinctions between this type of cap and the type formerly described. Firstly, there is no peripheral ridge corresponding to ridge 18, although such a ridge may be provided if required, and secondly the fingers, such as 23, have a tubular form. Again, the fingers are inclined extending downwardly towards lower edge 13 at a compound angle inclined to a radius at an angle a and to an axis normal to the radius and in the place of the wall at an angle {3.

In FIGURES 4 and 5 the method of mounting a cap in accordance with the present invent-ion is illustrated. The cap illustrated is of the form described with reference to FIGURES 1 through 3 but the method of applying is substantially the same with respect to the cap of FIG- URES 6 through 8. Only the upper part 24 of a container is illustrated and that in section. As shown the container comprises a tubular side wall 25- about the upper edge of which a top wall or breast 26 is secured. Top wall 26 slopes upwardly and inwardly and in the centre thereof a valve assembly 27 is mounted. Intermediate the height of top wall 26 a peripheral shoulder 28 is formed. It is with this shoulder that the fingers, such a513, 14, 15 and 16 of cap 10 engage.

Initially the cap 10 is placed over top wall 26 and then it is pressed down as the cap 10 is moved downwards the fingers such as 14 are deflected outwardly as they move over shoulder 28 and at the lower limit of the cap travel, that is when edge 13 engages the adjacent wall 26, there is firm engagement between the fingers and the underside of shoulder 28.

The compound angle of the fingers enables the cap to be applied without excessive effort at least relative to fingers which extend vertically inward. With such lastmentioned types of fingers, the forces on the finger act almost axially and a substantial pressure would be required to apply the cap. With the fingers of the present construction and inclination the force required to apply and also to remove the cap is substantially equal, and there is no undue need to stretch or distort the cap since the fingers move. The cap of the present structure may be slightly distorted but it is minimal due to the finger movement. The engagement with the can is also such that there is no interference with the valve operation and there is a reduced possibility of the cap being removed accidentally in transit by engagement with another can or cap.

The foregoing specification sets forth the invention in its preferred practical forms but the structure shown is capable of 'modification within a range of equivalents without departing from the spirit and scope of the appended claims.

I claim:

1. A cap for a dispenser having a top wall with a shoulder, said cap being formed from a resilient flexible material and comprising a top wall with a peripheral skirt depending therefrom, said skirt having a lower edge, and

.an inner surface, and a plurality of spaced apart projections having free ends extending inwardly from said inner surface, said projections being characterized in that they are inclined downwardly toward said lower edge of said skirt at a compound angle with respect to a radius of said cap and an axis normal to said radius which axis extends through plane of the skirt.

2. A cap for a dispenser as claimed in claim 1 wherein said projections have a frusto-conical form with the free end of said projections having a reduced diameter.

3. A cap for a dispenser as claimed in claim 2 wherein said skirt has a ridge extending about said inner surface adjacent the base of said projections.

4. A cap for a dispenser as claimed in claim 2 wherein projections are arranged in at least two series, each of said series having a first and a last projection, said first projections of each of said series being spaced apart from the adjacent last projection of the other series to provide at least two diametrically opposed gaps.

5. A cap for a dispenser as claimed in claim 1 wherein said projections are regularly spaced apart around said inner surface.

6. A cap for a dispenser as claimed in claim 5 wherein said projections are substantially tubular.

References Cited UNITED STATES PATENTS 3,136,453 6/1964 Patton et a1 220- 3,225,958 12/1965 Frankenberg 220'-60 THERON E. CONDON, Primary Examiner. JAMES B. MARBERT, Examiner. 

1. A CAP FOR A DISPENSER HAVING A TOP WALL WITH A SHOULDER, SAID CAP BEING FORMED FROM A RESILIENT FLEXIBLE MATERIAL AND COMPRISING A TOP WALL WITH A PERIPHERAL SKIRT DEPENDING THEREFROM, SAID SKIRT HAVING A LOWER EDGE, AND AN INNER SURFACE, AND A PLURALITY OF SPACED APART PROJECTIONS HAVING FREE ENDS EXTENDING INWARDLY FROM SAID INNER SURFACE, SAID PROJECTIONS BEING CHARACTERIZES IN THAT THEY ARE INCLINED DOWNWARDLY TOWARD SAID LOWER EDGE OF SAID SKIRT AT A COMPOUND ANGLE WITH RESPECT TO A RADIUS OF SAID CAP AND AN AXIS NORMAL TO SAID RADIUS WHICH AXIS EXTENDS THROUGH PLANE OF THE SKIRT. 